docs: def spawn_missing_classes(self, context=None):
          """
          Creates the appropriate python user relation classes from tables in the schema and places them
          in the context.
          :param context: alternative context to place the missing classes into, e.g. locals()
          """
          if context is None:
              if self.context is not None:
                  context = self.context
              else:
                  # if context is missing, use the calling namespace
                  frame = inspect.currentframe().f_back
                  context = frame.f_locals
                  del frame
          tables = [
              row[0] for row in self.connection.query('SHOW TABLES in `%s`' % self.database)
              if lookup_class_name('`{db}`.`{tab}`'.format(db=self.database, tab=row[0]), context, 0) is None]
          master_classes = (Lookup, Manual, Imported, Computed)
          part_tables = []
          for table_name in tables:
              class_name = to_camel_case(table_name)
              if class_name not in context:
                  try:
                      cls = next(cls for cls in master_classes if re.fullmatch(cls.tier_regexp, table_name))
                  except StopIteration:
                      if re.fullmatch(Part.tier_regexp, table_name):
                          part_tables.append(table_name)
                  else:
                      # declare and decorate master relation classes
                      context[class_name] = self(type(class_name, (cls,), dict()))
  
          # attach parts to masters
          for table_name in part_tables:
              groups = re.fullmatch(Part.tier_regexp, table_name).groupdict()
              class_name = to_camel_case(groups['part'])
              try:
                  master_class = context[to_camel_case(groups['master'])]
              except KeyError:
                  raise DataJointError('The table %s does not follow DataJoint naming conventions' % table_name)
              part_class = type(class_name, (Part,), dict(definition=...))
              part_class._master = master_class
              self.process_relation_class(part_class, context=context, assert_declared=True)
              setattr(master_class, class_name, part_class)